Abstract: A resonant rotationally oscillating mechanical system has masses supported by a resilient structure held at both ends on a stationary base to define a natural resonance frequency of intended rotational motion about an axis relative to the base. The resilient structure is asymmetrical along the axis. The masses are subject to additional motion relative to the base in directions different from the direction of intended motion. For a selected mode of motion, the masses and the asymmetrical resilient structure are mutually configured, in accordance with equations of motion, to substantially preclude angular motion of one of the masses relative to the base about an axis other than the axis of the intended rotational motion. In another aspect, the resilient structure has one end attached to the base by a coupler that permits that end to move relative to the base, but only at frequencies different from the natural resonance frequency of motion.

Abstract: A resonant scanner has at least one torsionally rigid damper located at at least one torsional node point of a torsion bar. At least one node of an unwanted vibrational mode is determined to be at a distinct node point, whereby the damper damps the unwanted vibrations while passing desired torsional oscillations. The damper serves as the only physical coupling of the torsion bar to the housing and damps transmission of vibrations into and out of the scanner. One or both ends of the torsion bar may be configured as the rotor of a motor. The rotor fits within but is not physically coupled to a bobbin coupled to the frame. Two coils are wound on the bobbin at approximate right angles to each other to minimize a cross-coupling between the coils.

Abstract: A resonant rotationally oscillating mechanical system has a plurality of masses supported by a resilient structure held at both ends on a stationary base to define a natural resonance frequency of intended rotational motion about an axis relative to the base. The resilient structure is asymmetrical along the axis. The masses are subject to additional motion relative to the base in directions different from the direction of intended motion. For a selected mode of motion, the masses and the asymmetrical resilient structure are mutually configured, in accordance with equations of motion, to substantially preclude angular motion of one of the masses relative to the base about an axis other than the axis of the intended rotational motion. In another aspect, the resilient structure has one end attached to the base by a coupler that permits that end to move relative to the base but only at frequencies different from the natural resonance frequency of motion.

Abstract: A surface scanning system defining an optical path for scanning a planar surface, in which an angularly moving scanner deflects a portion of the path, an optical element aligned with stationary portions of the optical path is driven in rectilinear sinusoidal motion for providing focus correction as the surface is scanned, and in which the sinusoidal motion of the optical element and the motion of the scanner are caused to be interdependent in frequency and phase. The sinusoidal motion of the optical element maintains accurate focus on the planar surface. In another aspect a device for moving an optical element in linear resonant motion includes a cantilevered resilient support structure arranged to permit only linear motion of the element, and means for driving the element resonantly.

Abstract: A flexural member (54) in a flexural pivot is secured by a mounting member (50) to a cylindrical shell (48). The flexural member extends through an aperture (58) in an armature (44), to which it is attached by a clamp (62) that clamps one end of the pivot member (54) and is fastened by bolts (86) to the armature (44). By locating the armature (44) and the bolts (86) near the middle of the flexure member (54) rather than toward its end, the moment of inertia of the system is minimized, and its resonant frequency is thus maximized.

Abstract: A surface-scanning system of the kind that defines an optical path and has a scanning assembly comprised of X and Y angularly oscillating scanners for deflecting a portion of the path, and first and second optical elements aligned with stationary portions of the optical path and driven in rectilinear oscillating motion along the path to provide focus correction respectively for the X and Y scanners. The X direction scanner is of the resonant type and has a mechanism for dynamically tuning its resonant frequency, the first optical element is mounted to oscillate in rectilinear resonant motion, and the tuning mechanism of the X direction scanner is arranged to receive a signal representing the oscillations of the first optical element and to tune the resonant frequency of the X direction scanner to synchronize its resonant motion with that of the first optical element.

Abstract: An angular position sensor for determining the angular position of a shaft relative to a fixed support to which the shaft is rotatably connected, including a pair of interactive sensor elements respectively on the shaft and on the support, the elements being arranged for cooperation so that an electrical characteristic of at least one of the elements varies in accordance with the relative rotational positions of the elements, the cooperation being between two corresponding axially directed surfaces, one on each of the elements, a rigid spacer between and engaged upon the surfaces, and another member for permitting motion of one element along the axis of the shaft, for preventing motion of that one element in other directions than along the axis, and for applying a biasing force tending to press the elements toward each other against the corresponding surfaces of the spacer, for contact, whereby the spacing between the surfaces is kept constant by the spacer.

Abstract: A strip chart recorder having cantilevered spring arms integrally molded with its rigid chassis. One set of spring arms maintains pressure on a paper drive nip, another set permits resilient deflection of a rod to latch a paper supporting door, and a third set resiliently retains the paper supply roll. Improved drive is obtained by movable mounting of the drive roll in a special relationship that causes it to react to resistance of the paper by tightening the drive nip pressure.